1. Field of the Invention
This invention relates to the field of hanger clamps for garment bags, also known as trolley clamps, and especially to a hanger clamp for removably mounting clothes hangers of varying diameters at the top inside of a garment bag.
2. Prior Art
Trolley clamps for mounting inside garment bags are known having various forms of jaw structures that grasp the hooked ends of clothes hangers placed in the trolley clamp. The objective is to prevent the hangers from dropping off the trolley clamp into the garment bag when the garment bag is jostled during transport. Typically, such trolley clamps have two jaw elements pivotable relative to one another on a horizontal axis at the back wall of the garment bag, and are provided with a clasp means whereby the jaws can be fixed against one another to bear against the hangers. Examples of pivoting jaw retaining clamps are disclosed, for example, in U.S. Pat. Re. Nos. 31,075-London et al (original patent No. 4,252,220); 4,640,414-Mobley et al; 4,618,058-Gregg et al; 4,363,388-London et al; 3,566,456-London; and 1,948,019-Ballentine. These disclosures vary substantially in their particulars, however, in each case there are two opposed jaws which engage all the hangers placed on the trolley clamp.
In movable-jaw trolley clamps, there is a problem with some clamps in that the hangers can be inadvertently dropped from the trolley clamp when the clamp opens because the lower jaw falls freely away from the upper jaw. At least the user is required to manipulate the trolley clamp using two hands, which makes it very difficult to manipulate hangers at the same time. In order to avoid problems, the London '388 patent and the London '075 patent provides retainers whereby the lower jaw can only drop to a limited angle relative to the upper jaw, thereby making it less likely that the hangers will be dropped. The '058 Gregg patent has a stationary lower jaw and a movable upper jaw, the upper jaw being movably hinged at the back of a rigid c-shaped frame in the clamp rather than being fixed to the top wall of the garment bag.
A previous commonly owned application Ser. No. 163,642 filed Mar. 3, 1988 and entitled "Hanger-Retaining Clamp for Garment Bags" discloses a different form of clamp having a stationary lower support bar and a movable means bearing down on the hangers over the whole length of the bar using an eccentric pivoting element.
British patent No. 1,122,257-Carl discloses a simpler form of rigid c-shaped trolley clamp. In Carl as in Gregg and in the aforesaid application, the rigid nature of the lower support bar of the trolley clamp prevents loss of the hangers by falling forward along a tilting lower jaw when the clamp opens. Carl lacks any positive means for retaining the hangers, instead having a closure at the extreme front of the trolley clamp such that hangers are at most only loosely retained within the internal space of the c-shaped frame. It will be appreciated that this loose retention of the hangers frequently will allow a hanger to escape. One could make the vertical opening in c-frame type clamps very narrow, thereby making loss of the hangers less likely. The drawback of this approach is that the hangers are also more difficult to insert and remove.
A basic difficulty with trolley clamps having two opposed jaws is that relatively complicated clasp structures are required to force the jaws to remain against one another to thereby hold the hangers in place. Even when the jaws are closed, the hangers hold the jaws apart at a space, whereby any thin hangers are only loosely held if thick hangers are clamped nearby at the same time. In Gregg, an eccentric tab pushes upwardly against the top of the c-frame to force an intermediate jaw downward within the opening defined by the c-shaped frame, and the jaws are at least partly made of resilient rubber or the like to better accommodate varying hanger thicknesses. The eccentric is jammed in place when the clip is closed. Among the remaining patents, each requires a pivotable loop element or bail attached to one jaw for reaching around and grasping a distal end of the other jaw, to hold the clamp closed. These clasp elements require the user to manipulate the trolley clamp with two hands, and may obstruct free access to the open end of the trolley clamp for placing and removing hangers.
According to the present invention, a relatively uncomplicated eccentric tab is provided at the front of a trolley clamp, the eccentric being arranged such that it never substantially obstructs the opening between the top and bottom of the c-shaped frame, whether the clamp is open or closed. This is accomplished by abandoning the concept of closeable opposed jaws in a trolley clamp, instead providing a plurality of movable retaining elements that are forced against one another to retain the clothes hangers in place by means of a force directed in a forward/backward direction along a support bar rather than upwardly or downwardly against the bar or like fixed jaw. As a result, each hanger is retained between two independent retaining elements which are inherently spaced correctly for any size hanger.
The eccentric of the invention for urging the retaining elements together is also mounted for linear displacement relative to its turning axis, with a spring or similar resilient element providing a substantial span over which the eccentric will exert a force against the plurality of movable hanger retaining elements between which individual hangers are placed. Inasmuch as the spacing between any two retaining elements alotted to grasping a particular hanger is wholly independent of the spacing of the elements grasping other hangers, large and small hangers can be mixed on a trolley clamp without compromising the security of their attachment. Individual clamp element spacing is a substantial improvement over the prior art jaw method, wherein the same jaws grasps all the hangers, thereby requiring resilient (e.g. rubber) jaw parts and/or allowing thicker hangers to keep the jaws apart and preventing a tight grasp of thinner hangers. Nevertheless, all the hanger retaining elements are brought together or "closed" around their hangers using a single simple and easily operated lever control.
The invention has the advantages of the convenience of a rigid c-shaped frame as in the British patent to Carl, the convenience of a simple tab operator as in Gregg '058 and furthermore enjoys clamping dimensions specific to any size of hangers, uniform or mixed.